In hospitals, clinics or similar institutions, the safe disposal of used needles, syringes or other medical devices is a major concern to health care personnel. There are many currently available sharps containers which are designed to receive and safely store used medical devices. It is important that these sharps containers be readily accessible to the physician or nurse so that the medical device may be quickly and safely disposed of after use. Additionally, due to the large number of sharps containers which are used for the disposal of medical devices, it is important that the container be inexpensive and simple to use.
There are generally two types of sharps container available. The first type of sharps container has a disposable inner container with a reusable top cover and outer housing. The second type of sharps container is a completely disposable container which is intended to be disposed of once it is full. Disposable sharps containers typically have a rigid base or body section which is designed to have a sufficient volume to receive and store a large number of medical devices therein. The bottom and side walls of the body section must be constructed of a rigid material to ensure that the needles or other sharp objects do not pierce the side walls of the base section. Additionally, due to the large number of sharps containers which are used in hospitals or other large medical institutions, it is preferable to ship and store the body sections and top covers of the sharps containers in a nested condition to reduce the expenses related to the shipping and storage of a large number of sharps containers.
The top cover of the disposable sharps containers are typically constructed of a semi-rigid plastic material so that the cover will have sufficient flexibility to be snapped onto the more rigid body member. Alternately, the cover may be constructed of the same material as the body member but may be molded so that the cover is thinner and therefore, more flexible than the body member. The top cover of the sharps container typically includes multiple openings therein with various flaps or access doors associated with the openings to prevent access to the used medical devices once they are deposited in the body section of the sharps container.
As shown and described in U.S. Pat. No 4,494,652 granted to Nelson et al, and U.S. Pat. No. 4,502,606 granted to Shillington et al, one common approach to limiting access through the opening-in the resilient cover is to provide a plurality of flexible flaps which allow the user to insert used medical devices through the opening in the top cover while forming a relatively small diameter opening which will prevent access to the previously disposed of medical devices. The Nelson patent also discloses a manually operable clamp member which includes a pair of finger panels which may be squeezed together to assist the user in removing the needle from a syringe or other medical device. FIGS. 1 and 2 of the Shillington et al patent shows a pair of commonly available wrench-type structures which are formed as part of the top of the sharps container.
U.S. Pat. No. 4,375,849 granted to Hanifli discloses a small portable sharps container which is designed to receive and store used needles from medical devices such as blood collection tube holders. The cap member disclosed in this patent includes a slot member or opening with a plurality of stepped notches on one side thereof to contact the needle hub of a needle to assist in the removal of the needle from the medical device. Additionally, a movable closure lid is disclosed which rotates about the slot member to allow the user to close the opening in the cap member when the sharps container is being transported by the user.
In many of the presently available disposable sharps containers, a needle hub receiving member is formed as a molded or integral part of the cover to reduce the cost of the sharps container. Because the sharps containers are designed to hold a relatively large number of used syringes and needles therein, and because the material is semi-rigid and low cost, it is possible that the needle hub receiving member may become worn out or torn before the sharps container is full. In these situations, the needle hub receiving member will not provide adequate frictional contact with the needle hub of the used needle and the user will be unable to safely remove the needle from the medical device. The user may then risk accidental contact with the used needle by manually unthreading the needle from the medical device, or if the user is in a hurry, they may place the entire medical device in the sharps container with the needle still attached to the medical device. If the needle remains attached to the medical device, the likelihood that a subsequent user of the sharps container will accidentally contact the used needle is increased and the sharps container will also hold fewer medical devices.
One consideration in the design and manufacture of sharps containers is that the body section of the sharps container must be sufficiently rigid to prevent needles or other sharp objects from piercing the side walls of the sharps container. As a result of this need for a rigid body section, the top cover must have sufficient flexibility to allow the top cover to be locked onto the top of the body section and to allow the flaps which surround the large opening in the cover to flex as the user inserts the syringe or other used medical device into the sharps container. This need for a flexible top cover must be balanced with the need for a top cover which is sufficiently durable to withstand repeated use of the needle hub receiving notch and the manipulation of the flaps without dramatically increasing the cost of the sharps container. Finally, there is a need for the design of the sharps container to be kept as simple and convenient as possible because the user may be monitoring the patient or performing other tasks while they are disposing of the medical device. Therefore, if the sharps container is too complex or requires additional manipulation of a member on the sharps container, the likelihood that the user may accidentally contact the used needle may be increased.
The nature of this problem may be better understood with reference to the use of a specific size product. For example, a number of companies market a relatively small four quart sharps container. This sharps container has an approximate capacity of 4 quarts and it is estimated that it may hold approximately 120 used 3 cc syringes. Therefore, if the institution requires that the user remove the needle from the syringe prior to disposal, the needle notch may be used nearly 120 times before the sharps container is full. Because the top cover of many of the currently available sharps containers are manufactured of a polypropylene material and the needle hub of many currently available needles are likewise manufactured of a polypropylene material having a similar or slightly higher hardness, the needle notch may deteriorate before the sharps container is full. If the sharps container is used in a setting where a large number of blood samples are drawn, the user will typically remove the blood collection needle from the blood collection tube holder after each use and reuse the blood collection tube holder for more than one patient. In this type of situation, it is likely that needle notch will be used more often than in the situation where the sharps container is used primarily for the disposal of used needles and syringes.